Two people were arrested June 8 after police found 36 packages of fentanyl in their vehicle during a traffic stop near Sister Bay.

Door County Sheriff's Department patrol units, with assistance from the Bailey's Harbor Town Constable, stopped a vehicle near Sister Bay after there were reports it was weaving along the road, said Sheriff Steven Delarwelle.

Susan M. Schulz, 39, of Northfield, Ill., was suspected of driving while drug impaired and arrested, according to court records.

Officers searched the vehicle and found a box containing 36 individually wrapped packages of fentanyl, syringes and needles, resulting in the arrest of the passenger and vehicle owner, a 39-year-old man from Glenview, Ill.

The value of the fentanyl is unknown, Delarwelle said.

It's not the first time someone has been arrested for possession of fentanyl in Door County, but it is uncommon, Delarwelle said.

"To have that coming into our county is a huge worry," he said.

Fentanyl is a synthetic opioid that is 50 to 100 times more potent that morphine, and is many times more potent than heroin, according to the information the department posted to its Facebook site.

Charges against the couple have not been filed by the Door County District Attorney.

The man was released after a bond hearing and the woman remains in jail for a prior arrest June 5, also related to driving while intoxicated.

On June 5, a Sturgeon Bay police officer observed Schulz's vehicle was drifting across the center line and initiated a traffic stop. Schulz was arrested on suspicion of drug impaired driving and a search of the vehicle found THC and drug paraphernalia, according to the court documents.

Schulz was released on bond and later arrested, again, June 8 after an erratic driving complaint — except this time, officers found fentanyl while searching the vehicle.

Her initial appearance in the earlier case is June 20 and she faces five misdemeanor charges including obstructing an officer, possession of THC and three charges for possession of drug paraphernalia.